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1、 Find the nth to last element of a singly linked list. The minimum number of nodes in list is n. Given a List 3->2->1->5->null and n = 2, return nod 阅读全文
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1、私有化构造器，不能直接创建，调用方法创建对象； 2、饿汉式：instance在类装载时就实例化 3、静态内部类： 阅读全文
摘要：
1、 Given an array of integers, find the subarray with smallest sum. Return the sum of the subarray. For [1, -1, -2, 1], return -3 2、 1、只需要求出最小值 2、利用su 阅读全文
摘要：
不大懂 1、 Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its 阅读全文